Your goals for a healthier, happier life can be achieved; you just need to lower your ambitions in order to change your habits. Instead of crafting dramatic resolutions which require great willpower, I urge you instead to start taking the smallest, achievable steps possible. Start small, very, very small, and you can build a new foundation for a healthy life.
One of my clients came up with this plan to help her control her weight and to "eat healthy" throughout the coming year. She did a lot of research and chose six "must have" habits that combined food choices with behavioral techniques to guide her on her way. Here's her plan; you might want to use it as a guide for your own journey.